Rifle handgrip with thumb rest



FIG. 1 is a right side elevational view of a rifle handgrip with thumb rest, showing my new design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 top plan view thereof;

FIG. 5 is a front elevational view thereof; and,

FIG. 6 is a rear elevational view thereof.

The broken line showing of a rifle stock, action, and a hand grasping the rifle handgrip is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a rifle handgrip with thumb rest, as shown and described. 